Building A House - A Simple Plan

Sunday, June 12, 2011

I've just finished installing the radiant heating pipe in the upstairs bathroom. The pipe I'm using is 1/2' PEX pipe with an oxygen barrier. (More on that in a later post.)

I'm working with a 500' roll of pipe, so I've made up a quick n' dirty unspooler out of a couple of long clamps and a piece of 4" ABS pipe. When installing the Pex pipe, it needs to actually be unrolled, as opposed to just laying the roll of pipe on the floor and uncoiling it. If you just uncoil it from the roll, it will get twisted and be almost impossible to work with. (Think of how a garden hose gets all twisted up when you just uncoil it.) By hanging it up and unrolling it, you don't get any twists in the pipe and it installs easily.

I began by putting the end of the pipe down through the floor and into the chase that goes down to the basement. Then I layed the pipe in the long, winding slot in the floor. When I got back to the beginning again, I cut the pipe with enough length to go back down to the basement again. The entire length of pipe was 130'. Eventually, the two ends of the pipe will get connected to the radiant heating manifolds in the basement.

Monday, June 6, 2011

Today I was preparing the bathroom floor for the radiant heating system. The first step was to lay down 8" wide strips of plywood such that there is a 5/8" gap between them. At the ends of the strips of plywood I've cut semi-circles out of plywood as well. The goal is to create a continuous pathway that the Pex heating pipe will lie in.

I've also installed aluminum heat transfer plates in the straight sections. As the name implies, the heat transfer plates will help to transfer the heat from the warm Pex pipe to the floor by spreading the heat over a larger surface area.

You can see a short length of white Pex pipe in the photo below. I just put that in there to test the fit of the aluminum plates, and it all fits fine.

Where the Pex pipe exits the floor and heads down towards the basement, I've put 1/4 circles made out of plywood under the opening in the floor. That ensures that the pipe bends downward without getting any kinks in it.

Saturday, May 28, 2011

I’ve recently finished installing my bathroom fan system. Rather than have an individual ceiling fan in each bathroom, I’ve installed a single remote fan to ventilate both bathrooms. The fan is installed in an area away from the bathrooms and exhausts out the roof. This results in a quiet and efficient system. I’ll put in a timer switch in each bathroom, so the fan can be set to run for 5 – 30 minutes and then shut off automatically.

The white vent pipe you can see in the photos is 4” PVC pipe. I’ve used the rigid PVC pipe rather than the flexible accordion-style pipe because the PVC pipe walls are smooth, so there is less air resistance than in the flexible pipes. The pipes run from both the bathroom ceilings to a Y-fitting on the intake side of the fan unit. The fan exhausts through a 6” diameter pipe to a roof vent. The 6” pipe is flexible aluminum pipe, but it’s only two feet long so there isn’t a lot of air resistance to deal with.

The fan I used is a Fantech FR 150. It’s rated at 263 cfm, which should be plenty for both bathrooms. It’s amazingly quiet. Even when standing right next to it, you can barely tell that it’s running. All you can hear is the air rushing through the pipes.

The ducting connections to the fan are sealed with aluminum duct tape. It's different than traditional duct tape; which will dry out and peel away. This is actually made of thin aluminum and will last for the life of the fan.

Friday, May 27, 2011

I've installed the roof vent for the bathroom fan system. I removed a couple of shingles and cut a round(ish) hole for the vent.

The top of the vent flange is tucked up underneath the roofing felt, and the new shingles get installed over top of that. I've used silicone sealant underneath the top and sides of the flange to ensure a good seal as well.

Tuesday, May 24, 2011

I've been installing the pink insulation baffles in the loft area. Their purpose is to ensure an air space is always present between the insulation and the bottom side of the roof sheathing. That air space is essential for proper roof ventilation.